1. Field of the Invention
This invention relates to a panel structure of a surface-discharge-type alternating-current plasma display panel and a method of driving the plasma display panel.
The present application claims priority from Japanese Application No. 2001-344070, the disclosure of which is incorporated herein by reference for all purposes.
2. Description of the Related Art
Recently, surface-discharge-type alternating-current plasma display panels have gained the spotlight as an oversized and slim display for color screen, and directed toward widespread use in ordinary homes and the like.
FIG. 14 to FIG. 16 are schematic views of a construction of a surface-discharge-type alternating-current plasma display panel in prior art, in which FIG. 14 is a front view of the surface-discharge-type AC plasma display panel, FIG. 15 is a sectional view taken along the V—V line of FIG. 14, and FIG. 16 is a sectional view taken along the W—W line of FIG. 14.
In FIGS. 14 to 16, the plasma display panel (hereinafter referred to as “PDP”) includes a front glass substrate 1, serving as the display surface of the PDP, having on its back surface, in order, a plurality of row electrode pairs (X′, Y′), a dielectric layer 2 covering the row electrode pairs (X′, Y′), and a protective layer 3 made of MgO and covering the back surfaces of the dielectric layer 2.
Each of the row electrodes X′, Y′ is constructed of a transparent electrode Xa′, Ya′ which is formed of a transparent conductive film with a larger width made of ITO or the like, and a bus electrode Xb′, Yb′ which is formed of a metal film with a smaller width assisting the electrical conductivity of the corresponding transparent electrode.
The row electrodes X′ and Y′ are arranged in alternate positions in the column direction such that the electrodes X′ and Y′ of each pair (X′, Y′) face each other with a discharge gap g′ in between. Each of the row electrode pairs (X′, Y′) forms a display line (row) L in the matrix display.
The front glass substrate 1 is situated opposite a back glass substrate 4 with a discharge-gas-filled discharge space S′ interposed between the substrates 1 and 4. The back glass substrate 4 is provided thereon with: a plurality of column electrodes D′ which are regularly arranged and each extend in a direction at right angles to the row electrode pair (X′, Y′); band-shaped partition walls 5 each extending in parallel to and between adjacent column electrodes D′; and phosphor layers 6 formed of phosphor materials of a red color, green color, and blue color, each of which covers the column electrode D′ and the side faces of the partition walls 5.
In each display line L, the partition walls 5 partition the discharge space S′ into areas each corresponding to an intersection of the column electrode D′ and the row electrode pair (X′, Y′), to define discharge cells C′ which are unit light-emitting areas.
Such surface-discharge-type alternating-current PDP generates images through the following procedure.
First, in an addressing period following a reset period for generating a reset discharge, a discharge (an addressing discharge) is selectively generated between one row electrode of each electrode pair (X′, Y′) (the row electrode Y′ in this example) and the column electrode D′ in each of the discharge cells C′. With occurrence of the addressing discharge, lighted cells (the discharge cell in which wall charges are generated on the dielectric layer 2) and non-lighted cells (the discharge cell in which wall charges are not generated on the dielectric layer 2) are distributed over the panel surface in accordance with an image to be displayed.
After completion of the addressing period, a discharge sustaining pulse is applied alternately to the row electrodes X′ and Y′ of each row electrode pair simultaneously in each display line L. Every time the discharge sustaining pulse is applied, a sustaining discharge is caused between the row electrodes X′ and Y′ in each lighted cell by means of the wall charges formed on the dielectric layer 2.
Ultraviolet light is generated by the sustaining discharge in each lighted cell, which then excites the red, green or blue phosphor layer 6 in each discharge cell C′ to thereby form a display image.
In the prior art three-electrode surface-discharge-type alternating-current PDP having the construction as mentioned above, an addressing discharge and a sustaining discharge are produced in the same discharge cell C′. That is, the addressing discharge occurs within the discharge cell C′ incorporating a red, green or blue color-applied phosphor layer 6 provided for emitting color light upon creation of the sustaining discharge.
Due to this interposition of the phosphor layer, the addressing discharge created in the discharge cell C′ is subject to various influences ascribable to the phosphor layer 6, such as discharge properties differing among phosphor materials of three colors forming the phosphor layer 6, variations in layer thickness produced in a step of forming the phosphor layer 6 in the manufacturing process of the PDP, and the like.
Hence, the prior art PDPs have a significantly difficult problem for obtaining equal addressing discharge properties in each discharge cell C′.
The three-electrode surface-discharge-type AC PDP as described above needs a large discharge space in each discharge cell C′ in order to increase the luminous efficiency. Therefore, the prior art typically adopts a manner of increasing the height of the partition wall 5.
However, if the partition wall 5 is increased in height for an increase of the luminous efficiency, the interval between the row electrode Y′ and the column electrode D′ between which the addressing discharge is caused is also increased. This gives rise to a problem of an increase of a starting voltage for the addressing discharge.
Further, the prior art three-electrode surface-discharge-type AC PDP as described above typically has a configuration in which a reset discharge, an addressing discharge and a sustain discharge are caused by the same row electrode (the row electrode Y′ in this example) and therefore a reset pulse for initiating the reset discharge, a scan pulse (select pulse) for initiating the addressing discharge and a discharge sustaining pulse for initiating the sustaining discharge are applied to the same row electrode Y′, so that a discharge current for the discharge sustaining pulse is output by using a driver for generating the scan pulse.
This configuration disadvantageously means that, in order to reduce current loss, a high-performance scan-pulse generation driver must be used. The use of the high-performance scan-pulse generation driver increases heating values of the PDP, which therefore requires a panel construction with a high capacity to dissipate heat.
Still further, the prior art PDP as described above has another problem of requiring an extra high-performance switch circuit for isolating a reset-pulse generation circuit from a sustaining-pulse generation circuit.